It has become increasingly common to package liquid products, particularly liquid food products such as water, milk, juice or wine, in packages of the collapsible type.
A package of the collapsible type means a package with a chamber which is defined by flexible walls and whose volume is dependent on the mutual position of the walls.
Before being filled, this type of package can be in a flat and sealed state. This makes it possible to sterilize the chamber of the package at the time of manufacture and, with the sterility maintained, to distribute the package to a filling plant, such as a dairy.
It is known to produce rolls made up of interconnected packages of the abovementioned type rolled up on a bobbin and to arrange such a roll in a filling machine.
Such a filling machine is known, for example, from WO99/41149. The document describes how the rolled-out web of package blanks is fed through the filling machine so as to arrive, in the proper order, at a station for cutting open a filling channel, at a filling station for filling each package, and at a sealing station for sealing the filled packages.
A filling machine usually represents quite a considerable investment and, for this reason, there is a need for filling machines of simple construction and also for filling machines with a high filling capacity, i.e. filling machines capable of filling quite a large number of packages per unit of time.
There is also a need for such filling machines of high capacity that are able to fill the packages under hygienic conditions, especially if the filling machine is designed for aseptic filling of the packages. For filling to take place under hygienic conditions, it is necessary for spills and splashes to be eliminated or in any event reduced.
U.S. Pat. No. 4,674,266 A discloses an apparatus comprising stations for opening, filling and sealing of bags. The apparatus comprises a transport unit for moving the bags between stations. The transport unit in turn comprises gripping elements that carry plates extending downward. The gripping elements are designed to grip side portions of the packages. The plates are intended to prevent a swinging movement of the bags. This solution, however, has a number of disadvantages. First, the ability to attenuate the swinging movements is limited, which results in problems with spills and splashes. Moreover, the plates make rapid gripping of the bags difficult, which has a negative effect on the speed of production.